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            <div><h4 class="title">
                <a name="asio.reference.async_completion.completion_handler_type"></a><a class="link"
                                                                                         href="completion_handler_type.html"
                                                                                         title="async_completion::completion_handler_type">async_completion::completion_handler_type</a>
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    <p>
        <a class="indexterm" name="asio.indexterm.async_completion.completion_handler_type"></a>
        The
        real handler type to be used for the asynchronous operation.
    </p>
    <pre class="programlisting"><span class="keyword">typedef</span> <span class="identifier">asio</span><span
            class="special">::</span><span class="identifier">async_result</span><span class="special">&lt;</span> <span
            class="keyword">typename</span> <span class="identifier">decay</span><span class="special">&lt;</span> <span
            class="identifier">CompletionToken</span> <span class="special">&gt;::</span><span
            class="identifier">type</span><span class="special">,</span> <span class="identifier">Signatures</span><span
            class="special">...</span> <span class="special">&gt;::</span><span class="identifier">completion_handler_type</span> <span
            class="identifier">completion_handler_type</span><span class="special">;</span>
</pre>
    <h6>
        <a name="asio.reference.async_completion.completion_handler_type.h0"></a>
        <span><a name="asio.reference.async_completion.completion_handler_type.types"></a></span><a class="link"
                                                                                                    href="completion_handler_type.html#asio.reference.async_completion.completion_handler_type.types">Types</a>
    </h6>
    <div class="informaltable">
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            <colgroup>
                <col>
                <col>
            </colgroup>
            <thead>
            <tr>
                <th>
                    <p>
                        Name
                    </p>
                </th>
                <th>
                    <p>
                        Description
                    </p>
                </th>
            </tr>
            </thead>
            <tbody>
            <tr>
                <td>
                    <p>
                        <a class="link" href="../async_result/completion_handler_type.html"
                           title="async_result::completion_handler_type"><span class="bold"><strong>completion_handler_type</strong></span></a>
                    </p>
                </td>
                <td>
                    <p>
                        The concrete completion handler type for the specific signature.
                    </p>
                </td>
            </tr>
            <tr>
                <td>
                    <p>
                        <a class="link" href="../async_result/return_type.html" title="async_result::return_type"><span
                                class="bold"><strong>return_type</strong></span></a>
                    </p>
                </td>
                <td>
                    <p>
                        The return type of the initiating function.
                    </p>
                </td>
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    <h6>
        <a name="asio.reference.async_completion.completion_handler_type.h1"></a>
        <span><a name="asio.reference.async_completion.completion_handler_type.member_functions"></a></span><a
            class="link"
            href="completion_handler_type.html#asio.reference.async_completion.completion_handler_type.member_functions">Member
        Functions</a>
    </h6>
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                <th>
                    <p>
                        Name
                    </p>
                </th>
                <th>
                    <p>
                        Description
                    </p>
                </th>
            </tr>
            </thead>
            <tbody>
            <tr>
                <td>
                    <p>
                        <a class="link" href="../async_result/async_result.html"
                           title="async_result::async_result"><span
                                class="bold"><strong>async_result</strong></span></a> <span
                            class="silver">[constructor]</span>
                    </p>
                </td>
                <td>
                    <p>
                        Construct an async result from a given handler.
                    </p>
                </td>
            </tr>
            <tr>
                <td>
                    <p>
                        <a class="link" href="../async_result/get.html" title="async_result::get"><span
                                class="bold"><strong>get</strong></span></a>
                    </p>
                </td>
                <td>
                    <p>
                        Obtain the value to be returned from the initiating function.
                    </p>
                </td>
            </tr>
            <tr>
                <td>
                    <p>
                        <a class="link" href="../async_result/initiate.html" title="async_result::initiate"><span
                                class="bold"><strong>initiate</strong></span></a> <span class="silver">[static]</span>
                    </p>
                </td>
                <td>
                    <p>
                        Initiate the asynchronous operation that will produce the result,
                        and obtain the value to be returned from the initiating function.
                    </p>
                </td>
            </tr>
            </tbody>
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    </div>
    <p>
        The <a class="link" href="../async_result.html" title="async_result"><code class="computeroutput"><span
            class="identifier">async_result</span></code></a>
        traits class is used for determining:
    </p>
    <div class="itemizedlist">
        <ul class="itemizedlist" type="disc">
            <li class="listitem">
                the concrete completion handler type to be called at the end of the
                asynchronous operation;
            </li>
            <li class="listitem">
                the initiating function return type; and
            </li>
            <li class="listitem">
                how the return value of the initiating function is obtained.
            </li>
        </ul>
    </div>
    <p>
        The trait allows the handler and return types to be determined at the point
        where the specific completion handler signature is known.
    </p>
    <p>
        This template may be specialised for user-defined completion token types.
        The primary template assumes that the CompletionToken is the completion
        handler.
    </p>
    <h6>
        <a name="asio.reference.async_completion.completion_handler_type.h2"></a>
        <span><a name="asio.reference.async_completion.completion_handler_type.requirements"></a></span><a class="link"
                                                                                                           href="completion_handler_type.html#asio.reference.async_completion.completion_handler_type.requirements">Requirements</a>
    </h6>
    <p>
        <span class="emphasis"><em>Header: </em></span><code class="literal">asio/async_result.hpp</code>
    </p>
    <p>
        <span class="emphasis"><em>Convenience header: </em></span><code class="literal">asio.hpp</code>
    </p>
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            <div class="copyright-footer">Copyright © 2003-2022 Christopher M. Kohlhoff<p>
                Distributed under the Boost Software License, Version 1.0. (See accompanying
                file LICENSE_1_0.txt or copy at <a href="http://www.boost.org/LICENSE_1_0.txt" target="_top">http://www.boost.org/LICENSE_1_0.txt</a>)
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